There is a need in the medical field for mixing various acidic solutions for a wide variety of medical clinical uses. Many of these solutions are prepared on site by mixing a predetermined amount of dry acid powder with a predetermined volume of water to produce an acid solution having a desired pH. Most of these prior art acid solution mixing systems require a great deal of laborious and time-consuming handling. For example, a dry acid powder bag must be opened and a volume of powder must be measured and placed into a suitable mixing container. Then a volume of water must be carefully measured and poured into the container for mixing, either by hand or by a motorized paddle or other mixing or agitating instrument.
Once the solution is mixed a portion thereof must be tested to determine that the proper pH or solution concentration has been achieved. Where a pre-measured dry acid bag is used in the production of solution, great care must be taken to ensure complete emptying of the bag to produce a predetermined volume of solution of the desired pH. If the pH or concentration of the solution is incorrect by even a small amount, the portions must be adjusted and re-mixed, since in medical applications such as hemodialysis even a small variation in pH can have catastrophic results. In these prior art mixing systems, even where some portion of the process is automated, there is a great deal of user-intensive labor required in the mixing process.
In many dry acid powder applications, the powder can have a tendency to clump or stick to the bag sides, thereby making complete emptying of a bag difficult. Usually a bag or bags must be carefully opened by hand and emptied into a receptacle or hopper for further processing and mixing. Obviously, this procedure requires a great deal of manual labor, particularly for large batches. Each bag must be carefully opened, emptied, taking care to make sure the powder is completely removed, and then discarded by hand. In large medical systems used for hemodialysis this procedure can be quite unwieldy and unreliable, requiring repeated testing and mixing to produce consistent solution batches.
Thus there is a need in the art for a dry powder bag opening system, for example an acid solution mixing system, that minimizes user labor while assuring complete bag emptying for each bag utilized, thereby providing consistent mixing, quality control, and accurate pH in each batch of solution being prepared.